It's been no secret that the original The Binding of Isaac: Rebirth dev team at Nicalis has been working closely with Edmund for over eight years. Since that time the team has developed two DLCs and now for Repentance we're working with three new talented members who help little Isaac continue to grow. You probably already have seen names like Jeremy, John, Simon, Adrian and Matt from the credits--and we'll interview them at a later time--but this week we want to introduce you to three of our newest members of the Isaac dev team. On the internet you might know them as _Kilburn (lead designer), LeatherIceCreme (designer) and NotYourSagittarius (artist). We've gathered together to get a better understand of their background and what they're doing to make the last DLC to your favorite video game. Before we start, the trio have a ton of interest things to share so we're going to break this interview into multiple parts. We'll be sharing some pre-production dev screen shots and art so this is your #nospoilers warning. You made proceed!
OK, now it's your turn, as we talked about we want to give little glimpse into the people who are making their favorite game. Can you each tell us a little bit about yourselves? _Kilburn (Vinh): I was born in the south of France from Vietnamese parents, my dad was a software engineer so we always had a PC at home for as long as I can remember, I was playing all kinds of DOS games as a kid. It didn't take long for me to realize I wanted to make games well actually, I was more interested in modifying them, adding stuff on top of them one of the games I played the most as a kid was Worms, I'd always dream about all the weird items and weapons I would add to the game if I could mess with its code in some way, it's probably the one game that really made me want to become a game dev. I only got into programming much later though, when I entered high school, at the time I had very limited access to my PC since you know... strict Asian parents so my main source of entertainment was a graphing calculator. I spent most of my free time trying to figure out how to get games onto it, and eventually I started making my own, nothing amazing obviously but it was something to pass the time that's where most of my knowledge of Lua and C++ comes from, actually then when When I entered college I got into this game called Garry's Mod, which wasn't so much of a game rather than an engine made to be modded, I made all kinds of small projects on it, including an attempt at a perfect replica of Team Fortress 2 which I eventually dropped after a year or two, I think still, I learned a lot from it, how a lot of game mechanics are implemented and how game engines work in general, and since I was studying IT in college at the time I got to apply a lot of what I'd learned as well So, yeah, long story short, got my masters degree in IT, had a brief programming gig at a petrol company, then Rebirth came out, stuff happened and now here we are. LeatherIceCreme (Nikola): My name is Nikola, I live in Serbia (not Siberia), I'm known on the internet as LeatherIceCream. My Isaac obsession started with me making animations of the Duke of Flies and "Isaac of Isaac: Reisaac" on youtube before becoming the room/enemy designer for Anitbirth. And today I'm still doing that but for the official game. I'm pretty glad about this turn of events as I really like Isaac and I also really like making video games. As a kid I would draw levels of my favorite PC games in a notebook treating it as a pseudo-level editor, so to this day I really like making levels/rooms. And because I like making levels I also like making enemies to put in them, so I'm very glad I get to do some of that for Repentance. I've made a few standalone games already, so I've had experience with my craft from there. I fell into making content for the actual Isaac game back before Rebirth was released in 2014. There was a mod for the original flash Isaac was called "The Community Remix Mod", I asked to join their dev team as soon as they released a trailer, and I contributed a couple of items to it. Shortly after Rebirth was release, I was invited to become a developer for the Rebirth port of that mod as well, which eventually became Antibirth. Some of the items from Community Remix that I made up even made it to Antibirth. I'm really not an "items idea guy" at heart, I'm more comfortable with the aspects related to level design rather than game progression. NotYourSagittarius (SAG): Hi, I'm the main sprite artist of the three of us. I live farther from the other members so my sleep schedule has always been a little topsy turvy. I'm fine with it though! My discovery of Isaac happened when I saw the original flash game on Steam. I had some extra money on hand so I thought why not, I bought it for gits and shiggles. I got hooked a tiny bit but then it snowballed and now Isaac shows up the moment I pick up something to draw with. I met Vinh and Nikola later on when Rebirth came out. We all had great ambitions to make this thing called Antibirth. I came up with the crazy idea of adding alternate floors for each chapter and I thought it was just a pipe dream. But it's a thing now, and that's badass, because you can achieve anything if you put your heart into it. And Antibirth was nothing but heart. Then Repentance happened. I was overjoyed. Our little monster is now official. Aside from Repentance, I also have an artistic background and I draw things on the side. How long I've been drawing I don't exactly remember. I just know that I've taken it a little more seriously early in my high school days. I attended college quite a while back, and I still do! Except in this unusual time everything is handled online, which hasn't been easy on the mind lol. I'm currently enrolled in an animation program. BACKSTORY TIME. When I was younger was often home alone doing my silly little tasks, like drawing on my sketchbooks and listening to music very loudly in my room. I had a bit of a strange upbringing - my mom insisted I should get a career in medicine like her one day, but now she and the other members in my family support the potential I have in art and I am very thankful for them. I'm gonna try my best to repay them back. Normally I live in the Philippines, but once the whole pandemic passes by, I'm planning to move to Canada when the time comes. Who knows, maybe I could meet up with some online friends I know that live there!
What is it that drew each of you towards Isaac? Vinh: An old friend of mine! I remember playing Super Meat Boy and thinking it wasn't really my kind of game, so when Isaac came out and I saw the same art style, it didn't really catch my attention either, until one of my friends threw the game at me and basically forced me to play it so he could watch. Then when I started getting into it I couldn't put it back down anymore. I've always had a thing for games that offer a large variety of weapons or items that let you play the game in different ways (hence Worms), so there was no way I could resist this. I could have walked right past this game without noticing it if that friend wasn't as pushy as he was. The theme really spoke to me as well, Isaac is a pretty familiar name since I was raised a Christian, and my mother is quite conservative as well (though thankfully she's never tried to stab me with a knife!). And while I wasn't too fond of the art style at first, it eventually grew on me and I came to really appreciate its simplicity. Nikola: Back in 2011 I saw a no commentary gameplay video of the original flash version of Isaac. The first item they picked up was Boom! and it gave Isaac a fuse on his head. I didn't know of the whole items appearing on Isaac's sprite thing in Isaac so I thought he always had a burning fuse on his head and it was metaphorical, as I knew Isaac's themes were quite depressing. I really liked the fact that the game looked like a flash game I'd play online for free, but the gameplay and art style were so great that it was elevated to a "real game", and it taught me that those things makes a game special. It was strangely inspiring to me, as I've been making small flash animations (and sometimes games) for years before finding Isaac. It was also the first piece of media that really got me interested in drawing gory and gross stuff. And the use of religious elements for items really peeked my interest too 'cus not a lot of games did stuff to that extent back then. SAG: Oh boy, where do I start. My younger self had an interest in dark themes and Isaac fit the bill perfectly, despite looking all cutesy and funny. I had a sketchbook filled with Isaac drawings but I don't remember where I left it. I think it's best I don't find it. Initially, I never found an interest in this game. I remember seeing the trailer and had zero clue what it was. It was on sale one day so I bought it for no reason. I can't really imagine what would happen if I never picked it up that day... For me, it's the weird style of Isaac that drew me to it. There's something absurd about a round and happy creature carried by flies. What did you think when we announced Rebirth and the artstyle, music and gameplay was changed? Vinh: I was so excited for it! I'd just completed Wrath of the Lamb when it was revealed and couldn't wait to experience more Isaac. The switch to a pixel art style was a bit jarring at first but it grew on me pretty quickly and I completely stopped thinking about it once the first few screenshots came out. Of course I was looking forward to all the new items the most and I remember taking apart every single one of Edmund's blog posts, looking for new items and trying to figure out what they did and how they worked. I also remember being really excited for all the new synergies the game would bring and any eventual new characters. SAG: This was very interesting because the idea of Isaac getting a remake felt unreal. I remember seeing some pictures on Ed's blog and it looked promising! I remember when Man VS Game was playing it at PAX and I was so excited to see all the new little things like Fatties and new room sizes. Needless to say I've never been so hyped about a smiling poop that whistles. I found the change to pixel art a bit strange but seeing how there's so many lovely and creative ways people are playing with the artstyle now, I think it's for the better! I can't imagine Antibirth being done in the original's artstyle...
Nikola: I did find the change in art style to pixel art weird at first, I was very fond of the flash Isaac art style as well as music, but Rebirth did grow on me quickly once I started playing it. Although I did have very high hopes for the attention to detail in rebirth art, as Ed's blog posts at the time really got me excited for the brand new game and it's improvements. I remember believing that the level of detail was going to be so high that in one of Edmund's early Q&As I asked him if the same enemy types will look slightly different depending on what area they appear in. So I'm glad that Antibirth/Repentance has that high attention to detail thanks to Vinh really liking that kinda stuff. Either way, I was incredibly excited for the game thanks to all those old blog posts.
The teams art has very quickly been able to integrate into the art style from the original team. SAG: I'd say it took quite a bit of time to fully grasp the artstyle. There's some very simple rules to follow but are difficult to master. Anti-aliasing and line thickness, for example, are simple concepts that can make or break a design. I'd say the trickiest part aesthetic-wise is trying to come up with a design that looks like something Ed would draw. I would sometimes study what Ed drew in the past and try to integrate some of his design elements along with a dash of my own style when I make sprites. Size of dash varies from 'too scary' to 'too anime'.

Technical wise, I'd say the toughest part is doing floor art or anything that requires lots of shades in general. Floor art is the most beautiful part of the game but it's also the hardest and least documented - many people struggle with it as a result. Someday I'd like to make an in-depth tutorial on how floor art works. I can't guarantee it but it's something I'd like to try. As for what software I use? Paint Tool SAI. It's the same program I use for drawing and it wasn't designed for pixel art but I use it anyway. Gotta stick with what you're familiar with or so they say... What is the design methodology when designing rooms? Nikola: I find it comfortable enough to make about 20-30 rooms per hour (that includes testing and tweaking each room multiple times). What tool you use is a matter of preference honestly, you just have to use what you're the most comfortable with, as I am definitely a creature of habit. The way I make rooms heavily relies on what new enemies/obstacles Vinh gives me to play around with. I try to make some basic rooms of varying difficulties with the new entities, then I make a bunch of rooms pairing those up with complimenting enemies. Sometimes I might even think up with interesting ways that new mechanic reacts to other mechanics to make the occasional interesting rooms.
A lot of the new content in Repentance is meant to be harder than the base game, so for many of the rooms I try to put the enemies far apart from each other. This way players with busted item combos don't clear the room as soon as they enter it. I also try to avoid putting spikes or other dangerous obstacles 2 tiles in front of a door, as to avoid players accidentally getting hurt when backtracking and not paying attention. How did you find working with the Isaac code base so far? Vinh: Oh I'll need to go back a few years for this one. When I got Real Platinum God in Rebirth, I immediately started taking the game apart to really understand how it works (is that okay to talk about?). This was my chance to add all the items I had in mind so how could I resist? It took me almost half a year to gain near full understanding of the engine, from there we started more and more items, then moved onto more ambitious things like enemies and levels, then we got a tiny bit carried away and Antibirth happened. After spending a couple years working with the Isaac engine unofficially, working on the Forgotten Booster and Repentance was basically like being in familiar territory and nothing really changed. I wouldn't be able to tell you how I make enemies and items, all I know is that I usually have a vague idea of what something in the game should do, then I type some code and it eventually does what I want. I can assure you I have no idea what I'm doing most of the time and Nik can probably confirm this, he's witnessed it for himself.
Sometimes it takes a lot of trial and error to get something that really feels right. The Forgotten is probably my second proudest achievement and I'm so glad he got a positive reception. He ended up quite different from his initial design, the soul was originally pink and didn't have a chain but we ended up making it blue once we decided it would be more interesting if it could only get soul hearts, and the chain was added to give an incentive to switch back and forth instead of staying as the soul and ditching the skeleton. My one proudest achievement? You'll have to wait until release for that one!
Are there room designs from Rebirth, Afterbirth or Afterbirth+ that you really enjoyed and tried to emulate? Nikola: For the sake of consistency I do try to look at Ed's previous rooms as a guide. To me it's almost like the older the rooms are the more "pure" they are to me, and I sometimes look at them for inspiration. I also like to sometimes reference old rooms from previous DLCs, mostly to draw parallels between the "Base path" rooms and the "Alternative path" rooms. As for what to look forward to: I play this game every day and I'm no pro. I'm the closest thing to a casual player on the team, and I like to play the game a little bit "relaxed". So when something I did in a room bothers me a bit too much or I think it could have been more fair, I tweak it accordingly.
You've been doing pixel art for a few years now. SAG: I've been doing pixel art since Rebirth came out. I found it an interesting subject to get my feet wet in. Eventually I branched out to other games that utilize pixel art like Nuclear Throne and to some extent, Enter The Gungeon. Making mods for other games is a fun challenge that really tests how well you can imitate their unique artstyles. In a similar way with Antibirth becoming official, there are those that push their skills to the absolute limit, and get their creations recognized enough to be put in the official game. Check out TF2 for example! They have a powerful community filled to the brim with boundless creativity. TO BE CONTINUED...